U.S. patent number 3,748,939 [Application Number 05/170,707] was granted by the patent office on 1973-07-31 for traversing film cutter.
This patent grant is currently assigned to Borden, Inc.. Invention is credited to Anthony Salvatore D'Amato, Sumner Sheldon Feinstein, Jerold Julius Golner, Eugene John Trunk.
United States Patent |
3,748,939 |
Feinstein , et al. |
July 31, 1973 |
TRAVERSING FILM CUTTER
Abstract
The apparatus includes a motor; a guide rod; a blade mounted for
reciprocable movement on the guide rod in response to the actuation
of the motor; and an actuating bar over which film is pulled and
which energizes the motor in response to the pressure applied to it
by the stretched film, the blade is returned to its starting
position when the pressure on the actuating bar is removed and the
rotation of the motor is thus reversed.
Inventors: |
Feinstein; Sumner Sheldon (West
Peabody, MA), Golner; Jerold Julius (Lowell, MA),
D'Amato; Anthony Salvatore (Chelmsford, MA), Trunk; Eugene
John (North Andover, MA) |
Assignee: |
Borden, Inc. (Columbus,
OH)
|
Family
ID: |
22620936 |
Appl.
No.: |
05/170,707 |
Filed: |
August 11, 1971 |
Current U.S.
Class: |
83/370; 83/524;
53/390; 83/614 |
Current CPC
Class: |
B26D
5/08 (20130101); B65B 61/06 (20130101); B65H
35/0086 (20130101); B26D 1/04 (20130101); Y10T
83/541 (20150401); Y10T 83/8691 (20150401); Y10T
83/8822 (20150401) |
Current International
Class: |
B26D
5/08 (20060101); B65B 61/06 (20060101); B65B
61/04 (20060101); B26D 1/01 (20060101); B26D
1/04 (20060101); B26d 005/08 () |
Field of
Search: |
;83/370,372,614,524,484
;53/390 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Meister; J. M.
Claims
What is claimed is:
1. Apparatus for severing sheet material comprising an elongated
cutter guide means over which the sheet material is directed in the
transverse direction, a cutting means associated with said cutter
guide means and movable therealong across the sheet material, a
drive means connected with said cutting means for moving same along
said cutter guide means to sever the sheet material, and a
yieldably mounted elongated actuating member disposed parallel to
the travel of said cutting means and ahead of said cutting means
for energizing said drive means in response to pressure applied by
the sheet material when it is pulled over said actuating member,
the sheet material first passing over said cutter guide means and
then over said actuating member.
2. Apparatus of claim 1, wherein said elongated member is disposed
parallel to and spaced from said cutter guide means to allow said
cutting means to move between said elongated member and said cutter
guide means, said apparatus including a main switch which is in a
normally open condition, said drive means being energized by said
main switch which in turn is actuated by said elongated member to
move said cutting means across the feed path of the sheet material
and back to its starting position in response to de-actuation by
said elongated member.
3. Apparatus of claim 2 which includes yieldable means for
maintaining said actuating means in spaced relationship to said
main switch, a pair of spaced pulleys and a cord stretched between
said pulleys, said drive means is coupled to one of said pulleys
and said cutting means is affixed to said cord and moves therewith
in response to the rotation of said pulleys and movement of said
cord.
4. Apparatus of claim 3 wherein said cutting means includes a blade
carriage which is frictionally affixed to said cord and a blade
removably secured to said blade carriage.
5. Apparatus of claim 4 including snubbers provided at both ends of
said cutter guide means for absorbing the impact force of said
blade carriage and an auxiliary switch disposed ahead of said blade
carriage when said blade carriage is in its starting position, said
auxiliary switch being provided for de-energizing said drive means
when said blade carriage is returned to its starting position.
6. Apparatus of claim 5 wherein said blade carriage includes a
projecting guard disposed over said blade which protects hands of
an operator from said blade, said blade carriage also includes a
plate for removably securing said blade to said blade carriage.
7. Apparatus of claim 6 which includes a housing within which are
disposed said cutter guide means, said pulleys, said main and
auxiliary switches and said snubbers, said drive means being
affixed on the exterior of said housing.
8. Apparatus of claim 7 wherein said blade carriage comprises a
pair of spaced parallel legs joined together at the bottom and
generally corresponds to a letter U, one leg supports said blade
while the other a depending lug, said depending lug has an opening
which slidably accommodates said cutter guide means and a recess
which serves to frictionally engage said cord.
9. Apparatus of claim 8 wherein said housing comprises four walls
disposed at right angles to each other and a slot, which permits
one leg of said blade carriage to enter interior of said housing,
at least a portion of one of said walls being disposed between the
two legs of the U-shaped blade carriage, said leg supporting said
lug being disposed within said housing while said leg supporting
said blade being disposed between said housing and said actuating
means.
10. Apparatus of claim 9 which includes end blocks disposed within
the opposite ends of said housing, each of said end blocks includes
a recess; said cutter guide means is an elongated rod which is
supported at both ends by said end blocks; and said elongated
member includes a lateral extension at each side thereof provided
with inwardly directed pins which removably fit within the recesses
in said end blocks.
11. Apparatus of claim 10 wherein said housing comprises a top and
a bottom mating L-shaped plate section, said top section being
removably secured to said bottom section and said end blocks, said
sheet material is a plastic film wound on a roll.
12. Apparatus of claim 11 wherein said drive means is a capacitor
motor, said main switch is a three lead micro switch which is
normally in the open condition, and said auxiliary switch is a
micro switch including a resilient lever which is depressed by said
blade carriage on its return to thus actuate said auxiliary switch
to de-energize said drive means, said resilient lever being of
sufficient stiffness to slow down said blade carriage on its return
to its starting position.
13. Apparatus of claim 2 wherein said drive means is a 1/50 HP
capacitor motor.
14. Apparatus for severing sheet material comprising a housing
disposed transversely to the feed path of the sheet material having
a pair of end walls; a pair of pulleys affixed at opposite ends
within said housing; an endless cord entrained over said pulleys;
drive means coupled to one of said pulleys; a normally open
three-lead micro switch mounted within said housing but partially
extending outside thereof for actuating said drive means; a guide
bar disposed in said housing and supported by said end walls;
snubbers mounted on ends of said guide bar to absorb impact force
of a blade carriage; a blade carriage slidably mounted on said
guide bar comprising a pair of spaced legs joined at the bottom,
one leg of said blade carriage extends into said housing and has a
lug provided with an opening slidably accomodating said guide bar
and a recess within which is frictionally engaged said endless
cord, while the other leg is disposed outside of said housing and
is provided with a blade; an auxiliary micro switch mounted within
said housing adjacent said blade carriage when the latter is in its
starting position to de-energize said drive means when said blade
carriage acutates said auxiliary micro switch on its return to the
starting position; an actuating bar removably mounted on said
housing and being spaced from said housing to permit said blade to
travel between said housing and said actuating bar to sever the
sheet material fed over said housing and said actuating bar, said
actuating bar being actuated by stretching the sheet material
thereover; yieldable means for maintaining said actuating bar in
spaced relationship to said housing and said three-lead micro
switch, said drive means is energized to move said blade carriage
from one end of the apparatus to the other by displacing said
actuating bar into contact with said three-lead switch, the blade
carriage is returned to its starting position by permitting said
actuating bar to be displaced to its original position when the
sheet material is severed.
15. Apparatus of claim 14 wherein said three-lead micro switch
includes a normally open and normally closed circuits, said blade
carriage is returned to its original position when said actuating
bar is relieved of pressure which has the effect of de-energizing
the normally open circuit and of energizing the normally closed
circuit to drive said blade carriage to its starting position.
16. Apparatus of claim 2 wherein said main switch is a three-lead
micro switch which is in a normally open condition and is actuated
by depression of said actuating member to move said cutting means
across said sheet material and back to its starting position, said
apparatus including an auxiliary micro switch to de-energize said
drive means when said cutting means actuates it on its return to
the starting position.
Description
This invention relates in general to a device for facilitating the
cutting and dispensing of strip material and, in particular, to a
new and useful cutting device adapted specifically for cutting thin
plastic film, such as polyvinyl chloride. The device comprises a
knife member driven across a feed path for the film by a driving
motor which is actuated by a bar when the bar is depressed by the
film. When the film is cut, pressure on the bar is relieved thereby
actuating the motor to return the knife member to its starting
position.
The present invention is an improvement over the known devices for
severing strip material or film, principally with respect to the
provision of means for automatically returning the cutting blade to
its initial position, and also in the arrangement which permits the
simple operation of the cutting mechanism after the film is
stretched over a tray for goods to be covered thereby. With the
inventive device, it is a simple matter to grasp the end of a
length of strip material and pull it off its supply roll as the
outer end is wrapped around the tray and to thereafter move the
strip material over the top of the tray and to locate the trailing
portion of the film in a position over a guide channel along which
a cutting knife is movable. An important feature of the invention
is the provision of an actuating bar which is designed to be
depressed easily by either the tray being covered or by the
stretched strip of plastic material which engages over the top
thereof, as the operator pulls the material away from its supply
roll. The actuating bar causes a driving motor to move a cutting
knife across to sever the strip material in response to being
depressed and as soon as the strip material is severed, the
actuating bar is released and this causes the motor to return the
cutting knife to its original position. On its return, the knife
actuates a micro switch which de-energizes the motor in order to
reduce the impact of the knife when it slams into the abutment.
This is a mechanical cutting device which affects physical severing
by means of a sharp blade maintained at ambient temperature. Since
the internal elements are substantially enclosed within the
housing, there is no danger of scraps of meat, or anything else
that is being packaged, falling into the device thus requiring its
removal. Another practical advantage of the present invention
relates to the construction of the cutting device which can be
easily disassembled for cleaning, examination or for replacement of
parts. To remove the actuating bar, all that is required is to
manually ease the pins of the actuating bar out of the recesses
provided in the end blocks. As for the cover plate, all that is
needed to remove it is the extraction of four screws with a
screwdriver. The fact that the device is constructed of stainless
steel, or other metal acceptable for food processing, also
facilitates cleaning and general maintenance thereof.
Accordingly, it is an object of this invention to provide an
improved device for facilitating the covering of small trays which
includes a blade member actuatable by the stretching of a plastic
film over a guide bar as the tray is being covered and means for
immediately returning the knife to its starting position after the
plastic film has been severed. It is another object to provide a
simple means, particularly for applying thin polyvinyl chloride
plastic film for covering disposable tray packages for food
products, such as meats, with which means it is a simple matter to
orient one end of the plastic film over one end of the package and
to direct the remaining portion across the top to cover the product
in the tray and then to position the trailing part over the
actuating bar at a spaced location from the tray alongside the
cutting blade whereby stretching of the film across the actuating
bar depresses the bar and energizes the motor to drive the knife
across and sever the film.
Accordingly, it is another object of the invention to provide an
improved device for cutting strip material, particularly plastic
film, which includes a movable knife driven across a feed path of
the film in response to the depression of the actuating bar located
adjacent the path and means for returning the knife to its starting
position. A further object of the invention is to provide a device
for facilitating the dispensing and cutting of sheet or strip
material, particularly thin plastic film or foil, which includes
means for guiding a length of the sheet material over a guide bar
to permit the end thereof to be withdrawn and engaged over a tray
to be covered, and an actuating bar alongside the guide bar which
is depressed by tensioning the sheet to cause the blade member to
move across the guide bar and cut the sheet material. A further
object of the invention is to provide a device for dispensing and
cutting thin plastic film which is simple in design, rugged in
construction, economical to manufacture, simple to clean and which
is adaptable to quick replacement of parts.
The various features of novelty which characterize the invention
are pointed out with particularity in the claims annexed to and
forming a part of this disclosure. For a better understanding of
the invention, its operating advantages and specific objects
attained by its uses, reference should be had to the accompanying
drawings and descriptive matter in which there is illustrated a
preferred embodiment of the invention.
FIG. 1 is a front perspective view of the device for cutting thin
sheets of various materials, especially plastic film, which may be
used to cover food products disposed in trays;
FIG. 2 is a front planar view of the cutting device with the
actuating bar and the cover plate removed;
FIG. 3 is a view of the cutting device taken along plane 3--3 in
FIG. 2;
FIG. 4 is a side view of the film cutting device illustrating the
relationship of the actuating bar to the yieldable means which
serves to move the actuating bar away from the micro switch and the
cover plate;
FIG. 5 is a perspective view of one of the end blocks;
FIG. 6 is a perspective view of the actuating bar provided with a
pin at each end which are inserted into the cooperating recesses in
the end blocks;
FIG. 7 is a perspective view of the blade carriage provided with a
blade; and
FIG. 8 is a general diagram of the electrical circuit which
activates the cutting device.
Referring to the drawings in particular, the invention embodied
therein comprises a device for facilitating the covering of small
disposable food trays 10 which are of an inexpensive material such
as pressed or foamed plastic, fiberboard and the like. The trays
are adapted to contain a food product such as meat 12 which is
covered with thin plastic film or foil material 14. This material
is preferably a clinging type plastic film such as polyvinyl
chloride.
The apparatus includes a mounting stand generally designated 16
which provides a mounting for a reel supply (not shown) of the
plastic film 14 which is fed outwardly in a horizontal path
indicated by the arrow 18 between guide rollers 20,22.
When tray 10 is to be wrapped or covered with a plastic film, outer
marginal edges of film 14 are grasped by hands 26, indicated in
dotted lines, and guided about the tray disposed on ramp 24 so that
the tray is enveloped by the film. A sheet of film is then severed
and the free end is brought under the tray and sealed by means of
heat supplied to ramp 24.
In accordance with this invention, there is provided an
automatically operable cutting mechanism located directly adjacent
to ramp 24 which includes an actuating bar 28 and reciprocable
blade carriage 30 mounted in housing 32. As shown in FIG. 6,
actuating bar 28 has an elongated form and is provided with a pair
of mounting ears 34 at its ends and a flange 36 at its bottom which
extends away from the operator. In order to maintain the actuating
bar away from a micro switch when the cutting device is in an
inoperable condition, as will be fully described, an abutment 37 is
affixed at the right lowermost portion of the actuating bar.
Abutment 37 contacts a spring or a yieldable bumper and thus
maintains the actuating bar spaced away from the micro switch,
unless a force is applied to the actuating bar, in which case, the
micro switch is actuated and the blade carriage is automatically
reciprocated. Outer portions of the mounting ears 34 have affixed
thereto inwardly directed pins 38, 40 which support and maintain
the actuating bar in operable relationship with the cutting device,
as will be described.
As is apparent from FIGS. 3 and 4, housing 32 includes cover plate
42, base plate 44 provided with flange 45, and end blocks 46,48
disposed on the base plate at its opposite ends and secured thereto
by suitable means, such as screws. The cover plate 42 is L-shaped
and has a depending flange 50 with one leg of cover plate 42
resting on flange 45. The base plate is also L-shaped and combines
with the cover plate 42 to form an elongated box-like structure.
The cover plate is affixed to the base plate and the end blocks by
four screws, which can be easily removed.
FIG. 7 shows that blade carriage 30 is a U-shaped member having a
pair of spaced legs 54,56 and a depending supporting lug 58 having
an open recess 59. As is evident from FIG. 3, blade carriage 30 is
slidably mounted on rod 60 which is supported by the end blocks
46,48 and extends from one end to the other of the cutting device.
The blade carriage reciprocates on rod 60 between snubbers 62,64,
shown in FIG. 2, which absorb the impact force when the blade
carriage is rammed thereagainst. The snubbers are cylindrical and
are slipped over the ends of the rod. Material for the snubbers is
selected so that it is sufficiently resilient to absorb the force
of impact. Suitable materials are plastics and rubbers.
FIG. 7 shows blade carriage 30 provided with blade 51, which can be
an ordinary Schick injector blade. Blade 51 is disposed in slot 53
of the blade holder and is maintained in a position by a removable
plate 55. In order to prevent cuts to the hands of the operator,
the blade holder has a protruding guard 57 which prevents fingers
from coming into contact with the blade.
Also mounted within the housing are a pair of spaced pulleys 66,68,
which are affixed to the base plate. These pulleys are positioned
at ends of the base plate and have entrained thereabout cord 70. As
is best shown in FIG. 3, the blade carriage is affixed to cord 70
by means of a frictional engagement between open recess 59 in the
blade carriage and the cord. This arrangement is very practical
when it is desired to replace the cord in that the blade carriage
can be easily detached from the cord by pulling the cord out of
recess 59.
Yieldable means which maintains the actuating bar spaced away from
the micro switch, and therefore, in an inactivate position, is a
spring or a yieldable bumper 61 positioned at the right extremity
of the cutting device in end block 48. Resilient bumper 61
cooperates with abutment 37 to position the actuating bar in spaced
relationship to the micro switch.
The motive force to rotate one of the pulleys is supplied by motor
72 affixed to the rear of base plate 44. A suitable motor for this
purpose is the Triem, Inc., 1/50HP, split-capacitor motor.
Automatic operation of the cutting device is controlled by main
micro switch 74 disposed at the left on base plate 44 and an
auxiliary micro switch 75 located towards the right end and also
affixed to base plate 44. Micro switch 75 includes deflector lever
76 and actuating button 78.
A simplified diagram of the circuit and the micro switches is
illustrated in FIG. 8. Switch 74 has a normally open (NO) and
normally closed (NC) circuits. The NO circuit, when actuated, moves
the blade holder from right to left while the NC circuit, returns
it to its starting position. Switch 74 is normally open and is
actuated when the actuating bar contacts actuating button 80. When
the main switch 74 is actuated, the NO circuit is closed and the
motor is energized to move the blade carriage from right to left,
as seen in FIG. 2. Snubber 62 absorbs the impact when contact with
the blade holder is made, and brings it to rest. In this position,
the normally closed (NC) circuit is inactive. When film is cut,
pressure on the actuating bar is released and resilient bumper 61
displaces the actuating bar to its normal position away from button
80 of main micro switch 74 and actuates the NC circuit by sending a
signal to the motor through the auxiliary micro switch 75, which is
in NC position. The motor is energized in the reverse direction and
returns the blade carriage to its starting position. On its return,
blade carriage depresses button 78 of micro switch 75 by deflecting
lever 76 to open the return circuit and thus de-energize the motor.
Although the motor is de-energized when the blade holder traverses
micro switch 75, the generated momentum slams the blade holder
against snubber 64 which absorbs the shock and brings the blade
holder to rest. In order to reduce the impact, deflecting lever 76
is purposely elongated and made of stiff metal to provide some
restraining force. The time that it takes to move the blade holder
from right to left and then back to its initial position is about
0.04 seconds.
In another embodiment of the apparatus described herein, retraction
of the blade carriage is accomplished by means of a spring. This
can be done in several ways, one of which involves a coil spring
wound on a pulley with the free end thereof attached to the blade
carriage. The motor is a one-way motor which is de-activated upon
moving the blade carriage from its initial position across the feed
path for the plastic film, to allow the spring to return the blade
carriage to its starting position.
* * * * *